In the last decade a great deal of cellular telephone infrastructure has been installed, and the use of cellular telephones for voice communication has become commonplace. Presently, there is an interest in enhancing the capabilities of existing cellular networks to enable high bandwidth consuming multimedia communications. It is anticipated such enhancements will enable a plethora of applications that are of benefit to consumers.
In order to contain capital expenditures rather that building entirely new networks, plans for upgrading existing cellular networks have been developed. In the case of the Global System for Mobile Communications (GSM) cellular systems General Packet Radio System (GPRS) is an enhancement that provides for low bandwidth data communications, and Enhanced Data Rates for GSM Evolution (EDGE) is a further enhancement that increases the bandwidth of GSM/GPRS systems. In spite of such enhancements, continued increases in usage of cellular networks continue to push the limits of signal channel capacity. One particular example of the need for increase signal channel capacity is in the area of multicast and broadcast services. Signal traffic is used in setting up multicasts and broadcasts. It is expected that in the near term, multicast traffic for carrying a variety programming such as sports, news, music, etc. will become popular and account for a significant fraction of network traffic. Although GPRS/EDGE is a suitable way to transport moderate data rate multicasts or broadcasts, it is inefficient for low bandwidth signaling.
Generally, it would be desirable to be able to effectively increase the signaling bandwidth of existing cellular networks without significant capital expenditures.